After buying my first digital SLR a few years ago, I found a great new use for my previous compact camera Canon Digital Ixus 400. I quickly realized that Ixus could actually serve me as a perfect camera for Time-lapse photography. During the past few years, I had been more that satisfied with its image quality so the only problem to solve was: How to trigger the camera automatically?, as it had no such functionality built in as it's quite common in today's cameras.

So I decided to make use of my old Psion 3c handheld (BTW, It's still a great piece of hardware, superior in many ways to the modern mobile phones and netbooks, but that's a completely different story) and brought to help the OPL programming language to automatically trigger the serial port of the Psion computer, which I then connected to the camera's shutter through an Opto-isolator. By far, the most difficult step was to disassemble the camera to hook up the wires. After that I had a fully functional time-lapse machine ready to use as you can see in the image below:

Although, I was quite happy with the setup above and had taken a great bunch of videos (2) with it, I started to think about something smaller and lighter, which could replace the whole Psion-thing. It was at the same time I learned about the Arduino project, which is a small easily programmable hardware platform for hobbyist that could be turned into a camera trigger with almost no effort. It all seemed quite promising, but I wanted to go even further, or smaller, if you like, and come across Atmel's ATtiny:

Using ATtiny, I could enjoy the comfort of the Arduino ecosystem, however, resulting in even more compact and less power hungry projects. That was exactly what I was looking for. So I started to wire things up. First, I made a working prototype involving Arduino itself, and then switched the Arduino into a programmer and loaded the original program into an ATtiny85 chip. It all worked perfectly on the breadboard:

Finally, I turned the prototype into a nice compact board powered by just a single CR2032 battery. I was more than satisfied with the result and moreover it all took me just a few days to finish without any previous experience with neither Arduino nor ATtiny. What a great platform!

Just for the sake of completeness, here are both the original Psion program and the one that drives Arduino/ATtiny: